Trap-door fitting.



A. H. BECKMAN.

TRAP DOOR FITTING.

APPLICATION FILED Aue.17. 1914.

I i-N @tw/OW ya BI w mijniimlhltsi TRAP-DOOR FITTING.

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To @ZZ wlw/m it may concern.'

Be it known that I, AUGUST H. BECKMAN, a citizen of the United States, and resident or" Madison, in the county or Dane and State of i/Visconsin, have invented certain new and useful improvements in Trap-Door Fittings; and l do hereby declare that the tollowing is a full, clear, and exact description thereot'. v

My invention has for its primary object to provide a simple, economical and effective balance combined trap door and run-way for manhole openings, the same being so constructed and arranged that wien the door is swung upwardly to open posit-ion the connected run-way will swing downwardly to form an inclined path, to a` tloor upon a lower plane than the structure carrying the manhole.

Specilic objects of my invention are to provide a link connected door and run-way which members are pivoted to the opposite ends of a manhole, whereby upon a closing or opening movement ot the door the runway serves as a counter-balancing member to facilitate easy manipulation or' the load. Thus when the device is manipulated the weight of the connected members is utilized, whereby easy operation will result. To provide a peculiar link connection between the swinging members, whereby the center of gravity of` said members is shifted when they are moved from an intermediate position, to thus cause the weight of the door to act as a lifting power for the .run-way, when the door is swung toward its opening position and the run-way weight will act as a closingl force, when the door is swung toward its closing position from the intermediate position mentioned.V Thus when the door is closed the run-way is swung up to the ceiling so as to render the floor space there-below clear ot obstructions.

rllhis invention is particularly designed to be applied to manholes of sidewalk cellars, wherein access mustl be had thereto for the delivery and discharge of commodities.

My invention, owing to its peculiar arrangement, will materially reduce the cost of manufacture of such devices, increase the etliciency or" the same and also provide a means for protectionY against accidents when Specification of Letters Patent.

Application led August 17, 1914.

Fatented Dec. 28, i915. Serial No. 857,065.

the manhole is open due to the peculiarly caged door construction to be hereinafter described.

As an exemplitication of my invention I have illustrated a door in hinge connection with a counter-balancing arm constituting a combination chute and ladder.

l/Vith the above and other minor objects in view the invention consists in certain peculiarities of parts and combination of mechanical elements as herein set forth with reference to the accompanying illustrations and subsequential claims.

Referring by characters to the drawings Figure l represents a sectional elevation of a manhole iitting embodying the features of my invention, the section being indicated by the line l-l of F ig. 2. Fig. 2 a cross section of the same, the section being indicated by line 2`2 of Fig. l, and Figs. 3 and 4 double cross section of modii'ied forms of the run-way or counter balance arm.

A represents a structure comprising a ioor or sidewalk provided with a manhole B, the same being transversely disposed with relation to the sidewalk and terminates adjacent to the street curbing C as shown. Under the sidewalk structure A, is a cellar having a Hoor D, the said cellar or under compartment being of any desired type.

The manhole is provided with reinforcing angle iron side strip l and an end strip Q, the vertical webs of which strips are extended upwardly -and are flush with the face of the sidewalk. The side strips l are transversely connected at the rear end of the manhole by an angle iron strip 2 having a horizontal iiange that projects inwardly and flush with the upper surface of the side wall, the said horizont-al flange being undercut for the purpose of forming a flush joint with a trap-door 3.

rThe trap-door is formed from a metal facing plate which facing plate is reinforced longitudinally by angle iron strips 4, 4:, as shown. rlhe metal facing of the door is beveled ofi at its rear end, to form a matched jointwith the horizontal 'flange of the manhole strip 2, when said door is `closed and the front tree edge of the door facing plate is also beveled, to eect a matched joint union with the metallic angle iron facing strip 2 in the manhole. The rear end of the trap-door 3 is pivoted in connection with the manhole, by means of studs 6, which studs project from the side strips 1 just opposite the reinforcing manhole strip 2. The studs are tted in apertures of the manhole side strips 4, whereby a pivotal union is effected between the rear end of the door and manhole frame. Rigidly secured to the downwardly inclined angle iron door strips Ll, are metal legs 7 which legs extend into the cellar compartment as shown. These legs also form members of cage-like side walls of the door, the side walls being built up from straps 8, 8, 8l which straps connect the legs and the depending web of the stay strips il. The cage side walls are further strengthened by truss bars 9 that connect the legs and straps 8, 8.

The front angle iron stay bar 2, of the manhole frame, is provided with depending ears 10, which ears carry a pintle rod 11. The pintle rod constitutes a pivotal support for the side rails 12 of a run-way, which run-way may constitute in some instances a single arm. The side-rails of the run-way are cross connected by treads 12', whereby the run-way forms a step-ladder, when the free end of the same rests upon the ioor D as shown in Fig. 1. The lower ends of the run-way sideV walls have pivoted thereto links 13, the opposite ends of which links are in pivotal union with the lower' ends of the legs 7. Thus it will be seen that the door is hinged at one Aend or side of the manhole, while the run-way or arm is hinged at the opposite side of said manhole and that these two swinging elements are in linked connection. The comparative weights of the door and run-way, taken in connection withthe arrangement of links, is such that when the door is in an intermediate position or approximately half way closed and the runway is in a corresponding intermediate position, they are counter-balanced. By this counter-balancing connection it is manifest that should the door now be swungtoward arfull closing position, the preponderance of weight will be such that the run-way will automatically rise and assume the position as indicated in dotted lines Fig. 1. It follows that should the door be swung in the opposite direction or to a full open position from the intermediate point mentioned, the preponderance of weight will be transferred to the counter-balancing arm or run-way, whereby Said runway will thereby be dropped, to the position indicated in full lines in Fig. 1, causing the door to be lifted to its full open position.

It is also desirable assnown in the accompanying drawings to. position the manhole with relation to the curbing of the sidewalk,

so that when the door is open the mouth formed by said door and its side caging faces toward the street or curbing, for the admission or discharge of commodities, and hence this opening, is to all intents and purposes, protected to prevent accidents by persons inadvertently falling into the manhole when so opened. lt will also be observed that by this counter-balancing arrangement the manhole fitting is so perfectly poised that it can be manipulated by the exertion of a few pounds of force, while with the ordinary constructed manhole doors the force necessary'is frequently so great as to require the application of motive power. As for example, as is suggested in Figs. 3 and 4 of the drawings, I may employ a run-way having treads 16, provided with. a chute 17 to one side thereof, whereby materials may be discharged into the cellar through said chute. It is also desirable in some instances treads in connection with the sideY rails 12 entirely, under which conditions a chute or trough 17 may as shown in Fig. 4 of the accompanying drawings be substituted for the the treads.

I claim:

1. A man-hole fitting comprising a man# hole frame, a. doorin pivotal union with one end of the man-hole frame, a guard frame extending from either side of the door and having depending legs that project through the frame, a run-way in pivotal union with the man-hole frame opposite the door pivot, and links connecting the legs and the/free end of the run-way. i

2. A man-hole fitting comprising a manhole frame, a door having side guards, the door being in pivotal union with the manhole frame, legs extending from the free end of the door through the man-hole, and a runway having side rails in pivotal union with the end of the man-hole frame opposite the pivoted point of the door, andlinks connecting the free end of the run-way side rails and door legs.

3. A man-hole fitting comprising a frame, a door in pivotal engagement withone end of the man-hole frame to form an upwardly swinging covertherefor, a counter-balancing arm in pivoting union with the opposite end of the man-hole frame adapted to swing downwardly, and a leg extending from the free end of the door and into the man-hole,

and a link connecting the leg and counter- 'A balancing arm whereby the weight. of the swinging cover Vand arm are neutralized coincident to 'movement of. said members.

4. A man-hole fittingcomprising a imanhole frame, a trap-doorv hinged thereto, downwardly extending guard legs depending from the free portion of the trap-door through said frame, truss bars and straps Y arranged in crossingrelation and connecting intermediate portions of the guard legs with the side edges ofthetrap-doorl to form an entrance cage, a run-way plvotally connected with the Inan-hole frame opposite the point the county of Dane and State of Wisconsin of connection of the trap-door with said in the presence of two witnesses.

frame, and link connections between the free end of the run-way and lower ends of AUGUST H' BECKMAN' 5 the guard legs. Witnesses:

In testimony that I claim the foregoing I MATH FIGY, have hereunto set my hand at Madison in FRANK BEIN.

Copies of this patent may be obtained for tive cents each, by addressin g the Commissioner of Patents. Washington, D. C. 

